1. Field of the Invention
This invention relates to a method and apparatus for processing photosensitive material and, in particular, to a compact table top apparatus for developing silver halide photosensitive materials, such as a sheet or web of photographic film or paper or plate, and its use.
2. Description of Related Art
In order to record an image onto a photosensitive material, such as a sheet or web of photographic film or paper or plate, typically the photosensitive material is first imagewise exposed, for example, to actinic light or electromagnetic radiation. Then the exposed photosensitive material is fed into a developing apparatus. In the developing apparatus, the exposed photosensitive material is processed as it passes through a series of developing, fixing and washing tanks which are usually arranged consecutively. The developed material is then dried. This process results in the image being permanently recorded on the photosensitive material.
Automatic developing apparatuses generally are large units suitable for industrial or laboratory environments. This is due to the mechanical complexity in accommodating the photosensitive material for both physical transport and processing through multiple solutions as well as service and maintenance requirements of the units.
Transport of the photosensitive material through the series of tanks must be closely controlled in order to accurately develop a quality image on the material. The apparatus typically comprises a transport mechanism having a multiplicity of rollers, gears and guides which are sometimes grouped together as racks for easy submersion into the appropriate processing tank. In addition, the developing apparatuses generally comprise a multiplicity of pumps, valves, drains, etc., which control, for example, the fill, replenish and recycle of the various chemical solutions and water throughout the apparatus. As such, developing apparatuses are generally complex, difficult to maintain and cumbersome to service.
Frequently, the chemical solutions, such as the developer used in the developing tank and the fixer used in the fixing tank, are purchased concentrated and must be diluted typically with water and mixed by an operator for use in the apparatus. Mixing of the solutions can be messy, from spills and splashes, etc., but also, and more importantly, mixing of the solutions exposes those individuals working with the solutions to the potentially hazardous and/or toxic chemicals.
Further, once the activity of a chemical solution is exhausted, i.e., the degree of chemical activity of the developer and/or fixer is low enough so as not to produce a quality image on the photosensitive material, the solutions are discarded from the apparatus via a drain typically permanently fixed ultimately to municipal water system. Concerns for the ecological safety of the environment question the disposal of such chemical solutions in such a manner.
Also, the processing solutions, especially the developer and fixer solutions, are typically maintained at temperatures above room temperature, for example in the order of 85.degree. to 120.degree. Fahrenheit (F) (29.4.degree. to 48.8.degree. Celcius (C)). The elevated temperatures of the solutions in prior art apparatuses give off a considerable amount of heat and vapors into the room where the apparatus is located. Additionally, developing apparatuses generally require high wash water throughput rates to keep the water in the washing tank clean. However, supplying the washing tank with a large amount of washing water at all times is highly uneconomical, does not meet demands for saving of resources and results in permanently piping water to the apparatus. Thus, typical developing apparatuses must be permanently located within a facility because of its requirements for drain, ventilation and utility services.
Various developing apparatuses have been proposed to address one or more of the aforesaid shortcomings of existing developing apparatuses. One in particular is U.S. Pat. No. 4,734,728 which discloses an apparatus for processing sheet films in which a drawer compartment is provided with a drawer or drawers which house insertable parallel containers of various processing solutions. All the processing solutions, including developer, fixer and wash water are supplied to their respective tanks via independent conduits with a circulating pump between the tanks and the drawers. Exhausted or waste processing solutions are directed to empty containers via a second series of independent conduits. The containers or drawers are automatically connected to the conduit upon its insertion into the drawer compartment. This apparatus, however, still has the disadvantage of requiring a considerable amount of plumbing conduits necessary for the transfer of processing solutions to and from their respective drawers, tanks and containers. Further, while all solutions are basically contained within the apparatus while in fresh through exhausted stages, there was no indication of reduced effluent or wash water volumes from conventional units.
It is an objective of the present invention to provide an apparatus for developing photosensitive materials which is compact, portable, office compatible, easy to operate and maintain, with low consumption of processing solutions and with low effluents in a self contained manner in order to reduce the human exposure to processing solutions and the environmental impact of the apparatus' operation.
It is an object of the present invention to provide a compact, table top, photographic film and paper processor that uses a reduced amount of replenishment and effluent of developer, fixer and water to allow this unit to be in an office environment versus the usual laboratory or industrial environment.
It is an object of the present invention to provide an apparatus capable of processing photosensitive material, such as a sheet or web of photographic film or paper, that does not require the water and drain services usually necessary for conventional photographic film and paper processors.
Further, it is an object of the present invention to provide an automatic photographic film and paper processor that uses pre-mixed chemistry cartridges and waste handling methods to eliminate chemical mixing and disposal methods currently required.